Finish surface and method of applying same



Jan. 22, 1935. R, E KELLEY y 1,988,450

FINISH SURFACE AND METHOD OF APPLYING- SAME- Filed July ll, 1931 IIII'IIIIIII Z2 6' @WMM/fl@ i INVENTOR WWW/@m ATTORNEYS Patented Jan. 22,1935 vFINISH SURFACE AND METHOD F APPLYING SAME Raymond E. Kelley,Snyder, N. Y., assigner to Helene T. Kelley, Snyder, N. Y.

Application .myI 11, 1931, serial No. 550,181

1 Claim.

This invention relates to a method of surfacing or finishing structuralsurfaces by mechanically applied process of permanently binding plaster,stucco or cement to concrete masonry of other structural surfaces insuch a manner as to positively prevent cracking, straining or theseparation of the finish from its base and also overcoming dampness andat the same time overcoming the plane o! cleavage.

The principal object of this invention is obtained by applying to thestructural surface to be plastered a coat of bonding material whichrenders the structure damp-proof and at the same time applying with thebonding material an inert material such as grit or sand blast sand whichis completely embedded and covered by the bonding material butv whichforms a roughened surface forming numerous keys so that when the plasteris applied it is keyed to the structure.

It has heretofore been proposed, as outlined in the Parkin Patent, No.1,282,460 to apply to the masonry surface a. coating of cold asphalt orother binding material and after such coating applied to blow againstthe coating a blast of sand or gravel, the sand sticking to the asphaltand forming numerous `keys for the plaster which is subsequentlyapplied. After such a surface has been applied, however, the weakness ofthe bond between the stone and the asphalt is readily made apparent whenthe surface is scraped with a stick or the like, the inert sand orgravel readily rubbing off and leaving the asphalt surface exposed. Thisweakness of the bond between the inert and the bonding materialcontinues after the plaster is applied and forms a plane of cleavagewhich is relatively weak so that the plaster in time cracks andy breaksaway. Moreover, in applying the sand or gravel to a ceiling very littleof the sand or gravel sticks to the asphalt coat- 4 ing so that inceilings not only is there a weak bond between the sand or gravel andthe asphalt but also there is a much smaller amount of sand or gravel toform keys for the plaster.

The present invention relates primarily to the improvement of the bondbetween the inert and the asphalt and is achieved by applying theasphalt and sand or gravel at the same time and in such manner that thesand or gravel is completely embedded in the asphalt and not merelystuck to it and at the same time the sand or gravel is large enough soas to form keys for the plaster. By this means the weak plane ofcleavage between the asphalt and the sand or gravel is eliminatedwithout in any way sacrificing the strength of surface to the upper faceof which it is desired to apply a coating of plaster, stucco or thelike. 10

Fig. 2 is a similar viewshowing a coating of asphalt and gravel appliedthereto, the gravel being completely embedded and forming keys for thesubsequent application of the plaster.

Fig. 3 is a similar view showing the plaster ap- 15 plied to thecoating.

Fig. 4 is a longitudinal section through a gun suitable for use insimultaneously applying asphalt and an inert substance in accordancewith the invention.

Fig. 5 is a longitudinal section taken at right angles to Fig. 4.

In Fig. 1 is illustrated a concrete or masonry structure 10 althoughitwill be understood that the invention can be carried out with any kind25 of a body or surface to which asphalt or other similar bondingmaterial will adhere. In apply- .ing plaster or stucco to such a bodythe first step,

in accordance .with thepresent invention, is to apply simultaneously acoating of cold asphalt 11 3o and sand or gravel 12. These two materialsare applied simultaneously and preferably by means of a suitable gun,such as is shown in Figs. 4 and 5.

This gun comprises a head 13 having an exter- '35 nally threaded nipple14 and an internal hollow stem 15, the tapered outer end 16 of whichprojects out through the nipple 14. On one side of the head anothernipple 17 is provided which connects with an air line 18, a passage 19leading 4o from this air line to the internal passage 20 of the stem l5.0n the opposite side of the body another nipple 21 is provided whichcommunicates with the interior of the nipple 14 and also connects with aline 22 supplying cold asphalt. 45 Over the outlet nipple 14 a cap ornozzle 23 is screwed. this nozzle having an opening 24 through which thetapered end of the stem 1511s adapted to project. It is apparent thatthe air issuing from the hollow stem 15 will draw out the bond- 50 ingmaterial and spray it upon the surface toward which the gun is pointedand that by screwing the nozzle 23 backwards or forwards the amount ofbonding material can be increased or reduced as desired. Formedintegrally with the nozzle 23 is an inclined sleeve 25 which is adaptedto receive a sand supply line 26, this sand supply line being directedtoward the center of the stream of air and bonding material issuing fromthe nozzle 23. The sand or gravel is applied under pressure and sinceall three streams are sprayed upon the surface at the same time thegravel or coarse sandlis'completely embedded in the asphalt and allsides of each piece of sand or gravel is completely embedded in theasphalt, as best shown in Fig. 2. By this means a strong bond isobtained between the inert and the asphalt and since the asphalt adhereswith great strength to the concrete or masonry surface a strong bond isobtained between the inert and the concrete or masonry structure.

From twenty to forty pounds of sand (this being from .20 to .44 cubicfeet, based on the weight of sand as 100 lbs. per cubic foot inMachinery's Handbook, sixth edition, and 90 lbs. per cubic foot given inKents Mechanical Engineers Handbook, tenth edition); to one gallon ofasphalt can be applied but preferably approximately one gallon ofasphalt is appliedto each thirty pounds of sand (.30 to .33 cubic feet)and it will therefore be apparent that the coating around each piece ofsand or gravel is'relativelythin and that therefore the sand or graveland asphalt surface' so applied is very rough; and forms numerousirregular keys or undercut indentations on its surface. This undercut,irregular. rough surface forms an excellent key and supportx for thecoating of plaster 27 which issubsequently applied, the plaster enteringinto the keyways and undercut indentations formed by the coated roughsand particles and being firmly united thereto. After the rst and second(scratch and brown) coats of plaster have set a finishing coat 28 can beapplied to the scratch and brown coat of plaster in the usual and wellknown manner.

From the foregoing it is apparent that a strong bond is obtained betweenthe asphalt and the concrete or masonry structural surface to which itis applied, a strong bond is obtained between the sand or gravel and theasphalt since the sand or gravel is completely embedded in the asphaltand at the same time the sand or gravel forms a very rough and irregularsurface which has numerous undercut indentations so that when theplaster coating is applied it is firmly keyed to the sand or gravel andasphalt coating thereby eliminating the plane of cleavage between thecoating and the plaster.

I am aware that coarse sand or gravel and cold asphalt have been appliedseparately to a structural surface, as previously described, withoutresulting disadvantage of a Weak plane of cleavage between the sand orgravel and the asphalt. The present invention therefore comprehends thesimultaneous application and embedding of sand or gravel in a coating ofasphalt in such manner that the sand or gravel is completely embeddedand at the same time forms a roughened key surface to which a plastercoating will be firmly bonded.

I claim as my invention:

The methodI of finishing and coating a structural surface which consistsin simultaneously forcing a spray of a relatively small amount ofasphalt and a stream of a relatively large amount of coarse sand againstsaid surface, said materials being applied in proportions of one gallonof asf phalt to. from .20- to .44 cubic feet of sand, said streammingling and said sand being coated with said asphalt while in the airand before reaching said surface and said asphalt forming 4a. coating onsaid surface and also causing the adhesion of the pieces of sand to saidsurface and providing voids between the grains of sand of suiilcent sizeto form a key or clutch for the reception of a plastic coating andsubsequently applying a plastic coating thereto.

RAYMOND E. KELLEY.

